Not long after Suzlon started selling wind turbines into China, now Germany's Nordex has the first multi-megawatt turbines now leaving the new joint assembly facility in Yinchuan. "This is a major step forward for us. Local production facilities are crucial for success in China in the future. And what we’re talking about is one of the world’s largest growth market," says Thomas Richterich, commenting on the delivery of the first 1.5 MW turbine. The Chinese government wants to increase the installed wind farm capacity from a current volume of around 1,500 MW to 30,000 MW by 2020.

It's curious how wind turbines have stopped getting bigger. 3 years ago, I wrote a paper for the Economic Research Council on the future and cost of renewable electricity entitled Recharging The Nation and I assumed that by 2010, 5 MW wind turbines would be standard. This has not happened. It is now thought that the optimal size for wind turbines is 2.5 MW or less. And manufacturing has still not moved from batch-processing to continuous manufacturing. To do so with massive 5 MW turbines is even less likely.

I still think though that really, really large wind turbines are the future. The logic is inescapable - double the size of the windswept area and receive eight times the power generation.

So wait for a fall in steel prices and go figure.